Immunology Flashcards
normal flora
bacteria that are always present in certain places of the body
dont cause harm (low virulence) at their intended site but can cause harm if somewhere else (opportunistic)
opportunistic pathogens
pathogens that only cause disease in immunocompromised states
only cause disease if given the opportunity
colonized
formation of population of microorganisms
carriers
individuals with pathogens in a significant number; acts a source of the infection
MAY not have symptoms
virulence
microbes ability to cause disease
ID 50
of organisms required to cause disease in 50% of population
individualized for ea. pathogen
LOW ID50 = HIGH Virulence
infection
presence of pathogen and/or symptoms of disease
may have presence of pathogen with out symptoms (subclinical) – due to immune response
endemic
persistent infections, usually low levels in specified areas
ex. of endemic
yearly, we expect about 13% of population in Jamaica to have malaria
epidemic
disease occurs at much higher rate than usual for a specified region
ex. of epidemic
500 cases of zika in cincinnati
expected zero
pandemics
infections that spread rapidly all over the globe
main entry points for human disease1
GI, respiratory, skin, genitals
two methods of human to human
direct and indirect contact
vector
LIVIING ORGANISM (I.E. tick or insect) that transmits disease from one to another
just carries disease, doesn’t get sick
direct contact
directly passes from person to person (i.e. via kissing)
indirect contact
passes from human to something else then to new person
non human to human methods of transmission
zoontes
fomites
zoonotic
pathogens hat utilize an animal reservoir to cause disease
i.e. Swine flu
animal is also sixk
fomites
inanimate objects that carry infection (clothes, utensils, furniture)
cough on a dirty tide and then touch the tissue
4 stages of disease
- incubation – from when you get it to when you begin to have symptoms
- prodrome – may or may not, non specific symptoms
- illness – characteristics of specific disease
- recovery/convalescence
main fxn of immune system
prevent or limit severity of infections
healthy system can distinguish self from foreign (autoimmune can’t)
immunodeficiency
occurs when there is a weakness or integrity of immune system so it allows pathogens to proliferate
esp. opportunistic pathogens
two types of immune system
innate and adaptive
innate immune
born with it
fully formed, prior to exposure
function quickly upon exposure in a non specific way
no immunologic memory
maintains barriers, macrophages
1st line of defense
chemical and physical barriers (skin and mucous membranes, fluid secretion, GI acid, coughing and sneezing)
innate
2nd line of defense
inflammation response (heat, redness, swelling, pain)
activation of complement
recruiting leukocytes and NK cells
presentation to adaptive
3rd line of defense
adaptive immune system
specific for a pathogen/antigen
takes several days before fully fxnl exposure
has memory
adaptive immune system two types of cells
b and t cells
b cells
generate the antibodies that recognize and inactive the pathogen
recruit cells to kill pathogen
generates both Abs and daughter plasma cells to have memory
steps in b cells once infected
presentation with Ag
proliferation to make Abs, plasma cells
Abs circulate in blood and come across infection
Ab binds and tags for inactivation and elimination
memory B cells k
cells that keep a stored copy of Abs so that it can be readily and rapidly copied upon repeat infection
speeds up reaction time of immune system
may decrease in levels if long time b/t infections
types of t cells
helper t cells
killer t cells
helper t cells
manages
non cytotoxic
facilities other cells to manage pathogens
killer t cells
recognize different antigen/ab completes
searches body to find them then induces apoptosis
who recommends immunization schedules?
ACIP and CDC
two classifications of immunizations
active and passive
active immunization
stimulates host to produce an immune response by stimulating B cell proliferation, Abresponse and T cell sensitization
vaccination
PREVENTATIVE
given to immunocompetent pts prior to exposure
goal is long term immunity, protects from disease
what are active immunizations derived from?
weakened live attenuated bacteria or virus, whole killed bacteria, or antigenic subunits of organisms
what happens at next exposure after adaptive immunization
there is a secondary responses that increases proliferation of B cells and formation of Abs
this is much faster and more effective
3 types of active immunizations
- inactivated
- live attenuated
- toxoids
inactivated bacteria vaccinations
most common
inert pathogens to engage immune system
ex. pertussis, flue, hap A, polio, meningococcal, typhoid
life attenuate bacteria vaccinations
weakened (low threshold so won’t get you sick)
contraindicated for immunocompromised or pregnant patients (due to ability to potentially cause disease)
ex. MMR, intranasal flu, oral typhoid, yellow fever, rotavirus, varicella
Toxoids vaccinations
bacterial toxins modified to make them nontoxic (not given Ag)
if exposed after vaccination, binds to toxin so that it is unable to cause disease
ex. tetanus and diphtheria
passive immunization
reactive
person is given Abs to a disease instead of producing them themselves
short term (weeks to month)
IM Ig
special consideration if given an active live virus vaccination bc it can combine to do nothing for patient
provides immediate protection to those who have been or will exposed to a pathogen
examples of passive immunization
administration fo IgG Abs via placenta or breast milk in newborns botulism IgG rabies IgG tetanus IgG
true contraindications for vaccination
- anaphylaxis
- immunocompromised or pregnant for live viruses
can have specific ones for a certain vaccine
precautions taken for vaccination
must weigh risk v benefit
if you are currently sick don’t want to overwhelm immune system
severe neurologic impa=irment after another vaccination (GBS or encephalopathy)
system for adverse event reporting
VAERS
who can report an adverse event
patients, parent/caregiver, providers
what counts as adverse event? 4
- anaphylaxis w/in several days
- encephalopathy, encephalitis, seizure
- squelae
- serious or unusual event
what do you consult when determining which vaccine to give?
immunization schedules released by CDC
routine childhood (12)
Hib b (heam. influenza B)
HepA
HepB
HPV
IPV (polio)
Flu
MMR
MCV (meningococcal)
PCV 13 (pneumonococcal)
RV (rotovirus)
VAR (varicella)
DTaP/Tdap (tetanus diphtheria and aceullar pertussis <7 and >7)
catch up schedule
used if a patient hasn’t had their vaccines routinely but would like to complete them
routine adult vaccinations
- influenza
- Td.Tdap
- Zooster (shingles, 60+)
- Pneumococcal (65+)
database for documenting vaccination
EMR
what is reported to EMR? (6)
- type of vaccine, dose
- site and route of administration
- date next dose due
- manufacturer and lot #
- name and address and title of administer
- date and time of administration
